November 25 | 2017
At the center of our own Milky Way galaxy lies a supermassive black hole named Sagittarius A*. Located about 26,000 light years from Earth, this black hole contains around 4.5 million times the mass of our Sun! Once a controversial claim, this astounding conclusion is now virtually inescapable and based on observations of stars orbiting very near the galactic center. Astronomers patiently followed the orbit of a particular star. Their results showed that the star was moving under the influence of the enormous gravity of an unseen object which must be extremely compact, and contain huge amounts of matter – a supermassive black hole. This Chandra X-ray telescope image shows the X-ray light from a region of space a few light years across. The black hole is invisible, but is near the center of this image. The gas near the center produces X-ray light as it is heated. Many of the ‘stars’ in the field probably have much smaller black holes near them that are producing the X-ray light from the gas they are consuming. Thanks for joining us for our 5th annual #BlackHoleFriday! Credit: NASA/CXC/MIT/Frederick K. Baganoff et al.
Observing images of craters on Mars provides scientists insight into the water that carved them and the Red Planet's history of water activity.
February 07 | 2018
What do you think this tadpole-shaped impact crater says about the water that used to fill it? Based on the terrain-height information and knowing that water always flows downhill, scientists were able to infer that the water in the tadpole crater was flowing down, and outward. The image was taken by the High Resolution Imaging Science Experiment (HiRISE) camera on our Mars Reconnaissance Orbiter. Image credit: NASA/JPL-Caltech/Univ. of Arizona #nasa #space mars